Dream Theater fans take note: There's a new prog-metal act in town, and you're going to want to add them to your listening list. Okay, California metal mavens Zero Hour aren't exactly new, considering that they are on their second album, but, hey, they're new to me!

When I mentioned Dream Theater, I didn't mean to label Zero Hour as a Dream Theater clone. They are a whole lot more. Sure, they fit under the same prog-metal umbrella, but these guys are much more progressive. Whereas DT's approach to prog metal is to mix progressive passages with more mainstream fare, Zero Hour pursues metal complexities relentlessly. Constantly changing meters drive compositions forward on a bed of rhythmic guitar crunch. They actually sound more like Spiral Architect than DT and somewhere between the two in complexity.

The rhythm machine of Mike Guy on drums and Troy Tipton on bass is as tight and wondrous a unit found in any prog metal outfit. These two play together like a single instrument -- an intense, driving force as much in the forefront of the music as it is the engine. This isn't to suggest that guitarist Jasun Tipton isn't an accomplished player. It's just that his guitar parts often seem to provide support for the driving bass and drum rhythms rather than the other way around. There aren't a lot of solos on this album. Instead, the guitar offers shimmering picked parts; pounding, chunky rhythms; or rapid-fire patterns. In any case, Zero Hour is one tight powerhouse unit.

Vocalist Erik Rosvold is a powerhouse himself, with the ability to move from low growls to intense wails to soft balladry with pure professionalism and aplomb. Like Dream Theater's James LaBrie, Rosvold has at his command several voices he can employ in order to deliver the band's musical message. He doesn't sound anything like LaBrie however, having a voice more similar to Ronny James Dio (remember him?).

I buy tons of progressive rock CDs and most of them are mediocre at best. I'm happy if out of ten discs, I find one worthy of steady rotation. Zero Hour is that one. Prog metal lovers will not want to miss The Towers of Avarice. Drummers and bass players, especially, who want to hear how their instruments can provide an intense rhythmic bed for a group's compositions should consider this album a must hear. This album is a proverbial encyclopedia of how it's done, and an intense listening experience to boot.